Windows 7: CPU fan not spinning

I bought a Cooler Master Hyper 212 + to keep my CPU cool and to make the PC quieter. Ive always used EPU-4 engine from asus to keep the computer from using its full power and turning it to full when I want to play a game etc. I had the computer running on low power consumption with the EPU-4 engine and noticed when I removed the CD drive panels that the fan wasn't spinning, I immediately switched the EPU-4 on to full to make sure that the fan was spinning, now its spinning at full speed.


This shows the temperature im getting with the fan on, With the fan off the Core temp is around 31c. Im assuming this is wrong and not sure what to do to make the fan spin all the time. Also wondering about the -128c temp any ideas why that's happening.

I've just had a look in the BIOS and it looks like the Core is the MB temp, Temp1 and Temp2 look like they are the CPU temp. I disabled Cool and Quiet to see if there are any differences, but it doesn't look like it. What I find strange is that I've been running the PC for about 5 days switching off at night with the fan off and it hasn't over heated or caused any problems.

It might have something to do with the fact that outside the US, and I believe the UK, pretty much most of the world uses the Celsius temperature scale.

@OP

I have had mixed results with EPU-4. I find that it's actually unreliable for my taste, so I disable it. Can't say I like Cool and Quiet either. That -128C temp you're seeing is pretty normal for Speedfan on an ASUS board. It looks like that particular sensor isn't at the addresses that Speedfan normally looks at. ASUS's PC Probe software will read most of the relevant details anyway, and it's useful for checking things out, but I don't let in run in the background.

I have two of those coolers, and to be honest, they don't always spin. If you have a well designed case with good cooling and cleaning wiring, it might not always spin. For example, on my new Sandy Bridge system, the fans spins when I boot up, and but comes to a stop soon after, and my proc temps are always good. Take the side off your case and watch the fan. Then load up a game or something intensive, and see if it kicks on. If so, you're fine.